Wireless communications systems are starting to make wider use of unlicensed spectrum. However, with the use of unlicensed spectrum, there is the uncertainty that the physical medium for transmission may not be available at the desired time of the intended wireless signal transmission. With paging operations in licensed spectrum, paging signaling from a base station can be scheduled, and it may be assumed that a paging request from a core node to a base station to page a UE is carried out. However, with unlicensed spectrum, the base station may be unable to transmit a core node requested page due to current unavailability of the unlicensed spectrum in the vicinity of the base station. This creates uncertainty at the core node requesting the page, since the core node does not know the reason that its page request has not been responded to. The core node can not efficiently make paging decisions, e.g., regarding expanding the page range, if the core node does not know the reason for the paging failure.
Wireless communications systems have been increasing the use of small cell base stations to augment the wireless coverage area, e.g., to provide coverage in dead zones within a macro cell base station's coverage area and/or to expand the coverage area beyond the outermost regions of the macro cell coverage, e.g., to fill in gaps between adjacent macro cells. Such a densification implies the number of small cells in a wireless communications system can be, and sometimes is, much larger, than the number of macro cells in the communications system. As the total number of small cells to manage with regard to paging (a given UE) becomes large, it becomes inefficient for the core network node, to try to individually manage and directly communicate with each small cell base station with regard to, for a given UE, sending paging requests and receiving paging responses.
Based on the above discussion there is a need for new methods and apparatus for supporting paging and particularly paging in communications systems including small cell base stations which use unlicensed spectrum.